Fibrous lost circulation material (LCM)

ABSTRACT

A human hair lost circulation material (LCM) is provided. The human hair LCM includes human hairs obtained from sources of human hair waste such as barber shops, saloons, beauty parlors, and religious sites. The human hair LCM may include human hair having a diameter in the range of about 50 microns to about 150 microns and human hair having a length in the range of 2 millimeters (mm) to about 4 centimeters (cm). Methods of lost circulation control using and formation of a human hair LCM are also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of and claims priority from U.S.Non-provisional application Ser. No. 16/267,659 filed Feb. 5, 2019, andtitled “FIBROUS LOST CIRCULATION MATERIAL (LCM),” a copy of which isincorporated by reference in its entirety for purposes of United Statespatent practice.

BACKGROUND Field of the Disclosure

The present disclosure generally relates to controlling lost circulationin a wellbore during drilling with a drilling fluid. More specifically,embodiments of the disclosure relate to a lost circulation material(LCM).

Description of the Related Art

Lost circulation is one of the frequent challenges encountered duringdrilling operations. Lost circulation can be encountered during anystage of operations and occurs when drilling fluid (such as drillingmud) pumped into a well returns partially or does not return to thesurface. While some fluid loss is expected, excessive fluid loss is notdesirable from a safety, an economical, or an environmental point ofview. Lost circulation is associated with problems with well control,borehole instability, pipe sticking, unsuccessful production tests, poorhydrocarbon production after well completion, and formation damage dueto plugging of pores and pore throats by mud particles. In extremecases, lost circulation problems may force abandonment of a well.

Lost circulation can occur in various formations, such as naturallyfractured formations, cavernous formations, and high permeableformations. Lost circulation can be categorized by the amount of fluidor mud lost as seepage type, moderate type, severe type, and total loss.The extent of the fluid loss and the ability to control the lostcirculation with an LCM depends on the type of formation in which thelost circulation occurs.

SUMMARY

Lost circulation materials (LCMs), also referred to as loss controlmaterials, are used to mitigate the lost circulation by blocking thepath of the drilling fluid (such as drilling mud) into the formation.Different types of LCMs are used to control loss of circulation.Depending on the morphological characteristics of existing LCMs, theycan be classified as fibrous, flaky, granular or their blends. Fibrousmaterials may be produced from biological sources or non-biologicalsources (that is, made synthetically). Non-biological fibrous materialsinclude synthetic fibers made from minerals, inorganic polymers andother inorganic materials. Fibrous materials produced from biologicalsources may be derived from plant and plant wastes or animal fibrouswastes.

Plant-based fibers may be weak, easily damageable and prone to quickbiodegradation. Plant-based fibers may also have poor thermal,mechanical, chemical and biological stability compared to other LCMs.Due to high temperatures, complex chemical environments, severemechanical degradation, and potential bacterial attack and degradation,plant-based fibers may be easily degraded in downhole conditions. Otheravailable biological fibers may also suffer from insufficient mechanicalstrength, chemical resistance, thermal stability, and biologicaldegradation. Consequently, existing LCMs formed may perform poorly atdownhole conditions and may not seal and block lost circulation zonesfor sufficient time periods.

Human hair waste generated by the cosmetic and other industries areconsidered as useless waste material and are typically disposed of inthe surrounding environments or in landfills. Due to wind and rain,water washing and other cleaning, the human hair waste may entermunicipal waste streams, drainage systems, and sewer systems where theycause blockage of drainage, sewer, and water lines. Such blockages cancause environmental and social problems, especially in areas withinefficient or poor waste management. The blockage of drainage, sewer,and water lines may also cause overflow of sewage and water intostreets, sidewalks, yards, and the other areas.

Other disposal approaches for human hair waste may be problematic. Forexample, disposal by the burning of human hair waste may not beenvironmentally friendly due to the release of certain gases such asammonia, carbonyl, sulfite, hydrogen sulfide, sulfur dioxide, andphenols, as well as ash into the atmosphere. The products released fromburning may be undesirable and create greater problems than the humanhair waste itself.

Embodiments of the disclosure include a human hair LCM used to mitigateor prevent lost circulation as well as provide seepage control andminimize or prevent fluid loss. The human hairs of the human hair LCMmay entangle, interweave, network, curl, and otherwise interact underpressure to form a plug or seal at openings of fractures, gaps,fissures, and cracks, in a lost circulation zone and prevent loss ofdrilling fluid. Advantageously, the production of the human hair LCM maybe relatively low cost (for example, lower capital investment and laborcosts) and may be less energy intensive as compared to the production ofother LCMs (for example, synthetic fiber LCMs).

A method to control lost circulation in a lost circulation zone isprovided. The method includes introducing an altered drilling fluid intothe wellbore such that the altered drilling fluid contacts the lostcirculation zone and reduces a rate of lost circulation into the lostcirculation zone, such that the altered drilling fluid includes adrilling fluid and a lost circulation material (LCM), the LCM includinga plurality of human hairs. In some embodiments, the altered drillingfluid consists of the drilling fluid and the LCM. In some embodiments,the LCM consists of the plurality of human hairs. In some embodiments,the LCM has a concentration in the range of 15 pounds-per-barrel (ppb)to 30 ppb in the altered drilling fluid. In some embodiments, each ofthe plurality of human hairs has a diameter in the range of 50 micronsto 150 microns. In some embodiments, each of the plurality of humanhairs has a medullary index in the range of greater than 0 and less than0.33. In some embodiments, the method includes adding the LCM to thedrilling fluid at a mud pit.

In another embodiments, an altered drilling fluid is provided thatincludes a drilling fluid and a lost circulation material (LCM), suchthat the LCM includes a plurality of human hairs. In some embodiments,the LCM consists of the plurality of human hairs. In some embodiments,the LCM has a concentration in the range of 15 pounds-per-barrel (ppb)to 30 ppb in the altered drilling fluid. In some embodiments, each ofthe plurality of human hairs has a diameter in the range of 50 micronsto 150 microns. In some embodiments, each of the plurality of humanhairs has a medullary index in the range of greater than 0 and less than0.33. In some embodiments, the drilling fluid is a water-based drillingfluid.

In another embodiment, a method of forming a lost circulation material(LCM) is provided. The method includes collecting a plurality of humanhairs from at least one waste source of human hairs, disinfecting aplurality of human hairs, and washing the plurality of human hairs afterthe disinfecting. The method also includes drying the plurality of humanhairs after washing and sorting the plurality of human hairs into atleast one group based on sizes of the plurality of human hairs to formthe LCM. In some embodiments, the at least one group includes threegroups, such that the three groups include a first group of theplurality of human hairs having respective lengths in the range ofgreater than zero and less than 10 millimeters (mm), a second group ofthe plurality of human hairs having respective lengths in the range ofgreater 10 mm and less than 20 mm, and a third group of the plurality ofhuman hairs having respective lengths in the range of greater 20 mm andless than 30 mm.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wellbore intersecting fractures of alost circulation zone in accordance with an embodiment of thedisclosure; and

FIG. 2 is a block diagram of a process for the production and use of ahuman hair LCM in accordance with an embodiment of the disclosure.

DETAILED DESCRIPTION

The present disclosure will be described more fully with reference tothe accompanying drawings, which illustrate embodiments of thedisclosure. This disclosure may, however, be embodied in many differentforms and should not be construed as limited to the illustratedembodiments. Rather, these embodiments are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art.

As a wellbore is drilled, a drilling fluid is continuously pumped intothe wellbore to clear and clean the wellbore and the filings. Thedrilling fluid is pumped from a mud pit into the wellbore and returnsagain to the surface. A lost circulation zone is encountered when theflow rate of the drilling fluid that returns to the surface is less thanthe flow rate of the drilling fluid pumped into the wellbore. It is thisreduction or absence of returning drilling fluid that is referred to aslost circulation.

Embodiments of the disclosure include a human hair LCM that includeshuman hairs to mitigate or prevent lost circulation in a well, as wellas provide seepage control and minimize or prevent fluid loss. The humanhairs may be obtained from sources of human hair waste such as barbershops, salons, beauty parlors, and religious sites. The human hair LCMmay include human hair having a diameter in the range of about 50microns to about 150 microns. In some embodiments, the human hair LCMmay include human hair having a diameter in the range of about 60microns to about 80 microns. In some embodiments, the human hair LCM mayinclude human hair having a length in the range of 2 millimeters (mm) toabout 4 centimeters (cm). In some embodiments, the human hair LCM mayinclude human hair having a length in the range of 8 mm to about 4 cm.In some embodiments, the human hair LCM may include human hair having amedullary index of greater than 0 but less than 0.33 As used in thedisclosure, the term “medullary index” refers to the ratio of themaximum diameter of the medulla to the maximum diameter of the hairshaft.

The human hair LCM may form tightly packed plugs and seals in cracks andfractures in lost circulation zones to provide improved control of theloss of whole mud from the borehole to the surrounding formation, ascompared to conventional and existing LCMs. The human hairs of the LCMmay provide for the formation of tightly packed, low permeability andpressure tolerant plugs and seals within the fractures, gaps, fissures,cracks, faults and other openings of a formation to prevent the loss ofwhole mud during drilling or other operations.

FIG. 1 is a schematic diagram 100 of a wellbore 102 intersectingfractures 104 and 106 of a lost circulation zone 108 (also referred toas a “loss zone”) in accordance with an embodiment of the disclosure. Aswill be appreciated, the wellbore 102 may be formed via a drill bit 110coupled to a drill string 112 that passes through the lost circulationzone 108. By way of example, FIG. 1 depicts open fractures 104 throughwhich a drilling fluid may be lost during drilling. In contrast, FIG. 1also depicts blocked fractures 106 blocked by a human hair LCM inaccordance with the techniques described in the disclosure.

The human hair LCM should be distinguished from animal hair that failsto provide the functionality and benefits described in the disclosure.Table 1 lists the physical and mechanical differences between human hairand animal hair:

TABLE 1 DIFFERENCES BETWEEN HUMAN HAIR AND ANIMAL HAIR Characteristic orProperty Human hair Animal hair Growth Pattern Grows independently Stopsgrowing after reaching specific length (usually less than about 3millimeters (mm) Physical Structure Soft and long; able to coil, Coarseand short; unable to loop, spiral and twist to coil, loop, spiral andtwist form seal or plug Filament-like structure Non-filament structureunable enables formation of to form effective seal or plug seal or plugFlattened and narrow Spinous or coronal cuticle scales cuticle scalesMedullary index Less than about 0.33; In the range of about indicativeof greater 0.5 to about 0.7 mechanical stability and thus greaterload-bearing capacity as compared to animal hair

Examples

The following examples are included to demonstrate embodiments of thedisclosure. It should be appreciated by those of skill in the art thatthe techniques and compositions disclosed in the example which followsrepresents techniques and compositions discovered to function well inthe practice of the disclosure, and thus can be considered to constitutemodes for its practice. However, those of skill in the art should, inlight of the present disclosure, appreciate that many changes can bemade in the specific embodiments which are disclosed and still obtain alike or a similar result without departing from the spirit and scope ofthe disclosure.

The following non-limiting examples of a human hair LCM were preparedand evaluated against an animal hair LCM. In the experiments describedsupra, the animal hair LCM is formed from goat hair. Plugging efficiencytests were conducted on the human hair LCM and the goat hair LCM using a2 millimeter (mm) slotted disc and a Permeability Plugging Tester (alsoreferred to as “PPT” or “Pore Plugging Test” apparatus) manufactured byOFI Testing Equipment, Inc., of Houston, Tex., USA. The tests wereconducted at conditions of about 212° F. and about 500 pounds-per-squareinch (psi) differential pressure. For the plugging efficiency tests, thehuman hair LCM and the goat hair LCM were incorporated into a 65 poundsper cubic foot (pcf) bentonite mud. The composition of the 65 pcfbentonite mud with mud components expressed in pounds-per-barrels(lb/bbl) is shown in Table 2:

TABLE 2 COMPOSITION OF 65 PCF BENTONITE MUD Mud Component lb/bbl Water340.67 Bentonite 25.00 Caustic Soda 0.25 Soda Ash 0.25

The bentonite mud, human hair, and animal hair were tested using thePermeability Plugging Tester apparatus and the following pluggingefficiency test procedure:

1. Set the temperature controller/thermostat to the testing temperature;

2. Check the condition of the O-rings in the groove at the top of thetest cell of the Permeability Plugging Tester apparatus and in the cellend cap and replace the O-rings if needed;

3. Apply a thin coating of high temperature grease to all the O-rings,including the two O-rings on the piston of the Permeability PluggingTester apparatus;

4. Screw the T-bar of the Permeability Plugging Tester apparatus intothe piston, install into the bottom end of the test cell, position thepiston about 1 inch into the cell bore, and remove the T-bar;

5. Add a volume of hydraulic oil to the test cell using the hydraulichand pump of the Permeability Plugging Tester apparatus;

6. Install all the O-rings and secure the end cap of the cell inposition such that oil flows from the hole in the end cap to ensure noair is trapped;

7. Install the valve stem into the bottom end cap of the cell, tightenthe valve stem, and disconnect from the hydraulic hand pump of thePermeability Plugging Tester apparatus;

8. Place the cell upright on a suitable stand;

9. Pour a test sample of a homogenous mixture of 275 milliliters (ml) ofthe 65 pcf bentonite mud and an LCM into the test cell;

10. Install an O-ring into the top of the cell below the 2 mm slotteddisc;

11. Place the 2 mm slotted disc on top of the O-ring;

12. Insert the end cap on the top of the disc, screw down the threadedretaining ring, and fully tighten;

13. Tighten the top stem of the test cell;

14. Place the cell into the heating jacket of the Permeability PluggingTester apparatus;

15. Connect a pressure hose from the hydraulic hand pump to the bottomof the test cell via a quick connector and ensure the bottom stem isclosed;

16. Connect the back pressure hose/sample collector to the top stem ofthe test cell, ensuring that the locking pin is in place, close thepressure relief valve on the side of the hydraulic hand pump, apply thetesting pressure via the back pressure regulator to the top of the testcell, and close the top valve.

17. Place a thermometer into the hole at the top of the test cell. waituntil the testing temperature is reached, and monitor the cell pressurewhile heating and bleed off pressure if necessary by opening thepressure relived valve on the side of the hydraulic hand pump;

18. Once the test sample has reached the testing temperature, pump thehydraulic hand pump until the pump gauge shows the testing pressure plusthe required back pressure;

19. Apply the required back pressure to the top of the cell, open thetop valve, and pump the hydraulic hand pump to reestablish the testingpressure;

20. To determine the spurt volume, collect the fluid from the backpressure collector in a measuring cylinder and record the amount,ensuring that all the fluid has been expelled;

21. Collect the fluid periodically over a 30 minute time period andcheck the back pressure gauge to ensure that the pressure remains lessthan the pressure threshold (about 3000 psi) of the built-in safety discof the Permeability Plugging Tester apparatus and avoid expulsion of hothydraulic oil;

22. Record the spurt loss, total leak off, and PPT values over the 30minute time period and record the cake thickness after dismantling thetest cell.

Table 3 shows the results of plugging efficiency tests for the 65 pcfbentonite mud without any LCM (that is, 0 parts-per-billion mass (ppb)LCM concentration), the example human LCM at 15 ppb and 30 ppbconcentrations in the 65 pcf bentonite mud, and the goat hair LCM at 15ppb and 30 ppb concentrations in the 65 pcf bentonite mud, with thespurt loss, fluid loss, total leak off, and PPT value measured in cubiccentimeters (cc) and the cake thickness measured in mm:

TABLE 3 PLUGGING EFFICIENCY TEST RESULTS FOR HUMAN HAIR MIX LCM AND GOATHAIR LCM Spurt Fluid Total Cake PPT Concen- Loss Loss Leak Off ThicknessValue LCM tration (cc) (cc) (cc) (mm) (cc) None  0 ppb All mud lostwithin a few seconds Human hair LCM 15 ppb All mud lost within 8 minutesHuman hair LCM 30 ppb All mud lost within 14 minutes Goat hair LCM 15ppb All mud lost within 3 to 4 minutes Goat hair LCM 30 ppb All mud lostwithin 4 to 6 minutes

As shown by Table 3, the bentonite mud without any LCM was lost from thePPT test cell within a few seconds after application of the 500 psidifferential pressure. At a 15 ppb concentration of human hair LCM, thebentonite mud was lost from the PPT cell at a slower rate than withoutany human hair LCM, and at a significantly slower rate at aconcentration of 20 ppb of human hair LCM. The human hair LCM thusdemonstrated a significant decrease in the rate of loss of the bentonitemud as compared to mud without the LCM.

The human hair LCM also exhibited superior mud loss performance ascompared to animal hair LCM. As shown in Table 3, at both 15 ppb and 30ppb concentrations, the human hair LCM exhibited significantly slowerrates of mud loss (that is, about half the rate of mud loss) than thegoat hair LCM at the same concentrations.

Human Hair LCM Manufacture and Use

In some embodiments, a human hair LCM may include human hairs. In someembodiments, a human hair LCM may consist of human hairs without anyother components. The human hairs include human hair obtained fromsources of human hair waste such as barber shops, saloons, beautyparlors, and religious sites. The human hair may be obtained frommunicipal waste streams (for example, from bathtubs, showers, basins),drainage systems, and sewer lines.

As will be appreciated, local sources of human hair may reduce the costof imported LCM products, components, or both. In some embodiments, thehuman hair may be prepared by cleaning the human hair before use orprocessing, such as by washing and disinfecting the human hair.

In some embodiments, the human hair LCM may include human hair having adiameter in the range of about 50 microns to about 150 microns. In someembodiments, the human hair LCM may include human hair having a diameterin the range of about 60 microns to about 80 microns. In someembodiments, the human hair LCM may include human hair having a lengthin the range of 2 millimeters (mm) to about 4 centimeters (cm). In someembodiments, the human hair LCM may include human hair having a lengthin the range of 8 mm to about 4 cm. In some embodiments, the human hairLCM may include human hair having a length of greater than zero and lessthan 10 mm and may be referred to as “fine grade.” In some embodiments,the human hair LCM may include human hair having a length in the rangeof about 10 mm to about 20 mm and may be referred to as “medium grade.”In some embodiments, the human hair LCM may include human hair having alength in the range of greater than 20 mm to about 30 mm and may bereferred to as “large grade.” In some embodiments, the human hair LCMmay include human hair having a medullary index of greater than 0 butless than 0.33.

In some embodiments, the human hair LCM may be added directly to adrilling fluid, such as a drilling mud, to create an altered drillingfluid having the human hair LCM. For example, in some embodiments, thehuman hair LCM may be added to (for example, blended with) an oil-baseddrilling mud or a water-based drilling mud. In some embodiments, thehuman hair LCM may be added at the mud pit of a mud system. In someembodiments, the human hair LCM may be added in an amount in the rangeof about 15 ppb to about 30 ppb. In some embodiments, the human hair LCMmay be added in amounts greater than 30 ppb, such as in the range of 30ppb to 40 ppb, or in the range of 40 ppb to 50 ppb.

After addition of the human hair LCM to a drilling fluid, the altereddrilling fluid may be circulated at a pump rate effective to positionthe altered drilling fluid into contact with a lost circulation zone ina wellbore, such that the human hair LCM alters the lost circulationzone (for example, by entering and blocking porous and permeable paths,cracks, and fractures in a formation in the lost circulation zone, suchas forming a structure in a mouth or within a fracture).

As noted in the disclosure, the human hair LCM may prevent degradationof the LCM while circulating downhole in the drilling fluid. Moreover,the non-toxic and environmentally friendly properties of the human hairsin the human hair LCM may minimize or prevent any environmental impactand effect on ecosystems, habitats, population, crops, and plants at orsurrounding the drilling site where the human hair LCM is used.

FIG. 2 depicts a process 200 for the production and use of a human hairLCM in accordance with an example embodiment of the disclosure. As shownin FIG. 2, human hair may be collected (block 202), such as from sourcesof human hair waste such as barber shops, saloons, beauty parlors, andreligious sites. In some embodiments, the human hair may be disinfected(block 204), such as using alcohol, ammonia, or other sterilizationtechniques that do not destroy the human hair. The human hair may thenbe washed (block 206), such as by a high pressure water or air jet, toremove disinfectant, dirt, dust, and other foreign substances. Thewashed human hair may be dried (block 208), such as by sun-drying over atime period at atmospheric conditions or using an oven.

In some embodiments, the dried human hair may be sorted and graded intodifferent sizes of human hair LCM (block 210). For example, in someembodiments, the human hair may be sorted and graded into the followingsizes: a length of greater than zero and less than 10 mm (“fine grade”),a length in the range of about 10 mm to about 20 mm (“medium grade”),and a length in the range of greater than 20 mm to about 30 mm (“largegrade”).

In some embodiments, the human hair may be packed for transportation anduse (block 212). For example, the human hair may be packed inwater-proof bags. In some embodiments, a suitable amount of packed humanhair may then be transported to an oil and gas operations site for useas a human hair LCM.

In some embodiments, the human hair LCM may be added directly to adrilling fluid, such as a drilling mud, to create an altered drillingfluid having the human hair LCM. For example, in some embodiments, thehuman hair LCM may be added to (for example, blended with) an oil-baseddrilling mud or a water-based drilling mud. In some embodiments, thehuman hair LCM may be added at the mud pit of a mud system. Afteraddition of the human hair LCM to a drilling fluid, the altered drillingfluid may be circulated at a pump rate effective to position thedrilling fluid into contact with a lost circulation zone in a wellbore,such that the human hair LCM alters the lost circulation zone (forexample, by entering and blocking porous and permeable paths, cracks,and fractures in a formation in the lost circulation zone). The humanhair LCM may entangle, interweave, network, curl, and otherwise interactunder pressure to form a plug or seal at openings of fractures, gaps,fissures, and cracks, in a lost circulation zone. In some embodiments,the reduced rate of lost circulation may be negligible. In someembodiments, the human hair LCM may be introduced via an open endeddrill pipe to place the LCM in the lost circulation zone. As compared toavailable LCMs, the plugs and seals formed from human hair may beresistant or impervious to mechanical, thermal, chemical, and biologicaldegradation at both surface and downhole conditions.

In other embodiments, the human hair LCM and one or more additional LCMsmay be added to a drilling fluid, such as a drilling mud, to create analtered drilling fluid having the LCMs. For example, in someembodiments, the human hair LCM and one or more additional LCMs may beadded to an oil-based drilling mud or a water-based drilling mud.

In some embodiments, the human hair LCM may be mixed with a carrierfluid, a viscosifier, or both. In some embodiments, a human hair LCMhomogenous suspension or pill may be formed. For example, a specificcarrier fluid, viscosifier, or combination thereof may be selected toform a homogenous suspension or pill having the human hair LCM. Thehomogenous suspension or pill may be added to a drilling fluid and usedin the manner similar to the human hair LCM described in the disclosure.

Ranges may be expressed in the disclosure as from about one particularvalue, to about another particular value, or both. When such a range isexpressed, it is to be understood that another embodiment is from theone particular value, to the other particular value, or both, along withall combinations within said range.

Further modifications and alternative embodiments of various aspects ofthe disclosure will be apparent to those skilled in the art in view ofthis description. Accordingly, this description is to be construed asillustrative only and is for the purpose of teaching those skilled inthe art the general manner of carrying out the embodiments described inthe disclosure. It is to be understood that the forms shown anddescribed in the disclosure are to be taken as examples of embodiments.Elements and materials may be substituted for those illustrated anddescribed in the disclosure, parts and processes may be reversed oromitted, and certain features may be utilized independently, all aswould be apparent to one skilled in the art after having the benefit ofthis description. Changes may be made in the elements described in thedisclosure without departing from the spirit and scope of the disclosureas described in the following claims. Headings used in the disclosureare for organizational purposes only and are not meant to be used tolimit the scope of the description.

What is claimed is:
 1. An altered drilling fluid, comprising: a drilling fluid; and a lost circulation material (LCM), wherein the LCM comprises consists of a plurality of human hairs.
 2. The altered drilling fluid of claim 1, wherein the LCM comprises a concentration in the range of 15 pounds-per-barrel (ppb) to 30 ppb in the altered drilling fluid.
 3. The altered drilling fluid of claim 1, wherein each of the plurality of human hairs has a diameter in the range of 50 microns to 150 microns.
 4. The altered drilling fluid of claim 1, wherein each of the plurality of human hairs has a medullary index in the range of greater than 0 and less than 0.33.
 5. The altered drilling fluid of claim 1, wherein the drilling fluid comprises a water-based drilling fluid.
 6. A method of forming a lost circulation material (LCM), comprising: collecting a plurality of human hairs from at least one waste source of human hairs; disinfecting a plurality of human hairs; washing the plurality of human hairs after the disinfecting; drying the plurality of human hairs after washing; sorting the plurality of human hairs into at least one group based on sizes of the plurality of human hairs to form the LCM.
 7. The method of claim 6, wherein the at least one group comprises three groups, the three groups comprising: a first group of the plurality of human hairs having respective lengths in the range of greater than zero and less than 10 millimeters (mm); a second group of the plurality of human hairs having respective lengths in the range of greater 10 mm and less than 20 mm; a third group of the plurality of human hairs having respective lengths in the range of greater 20 mm and less than 30 mm. 